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Introduction
As humanity uses up many of its non-renewable resources, there is a rising
interest in renewable energy sources. True, solar and wind energy have been around for a
while and they are being used increasingly, but there is one more renewable resource that
has not seen much attention: hydro energy.
Due to the energy crisis around the world, scientists work hard to find any
alternative energy source. Because of that, hydropower has increased in interest, usage,
and activity. There are many different types of hydro-powered devices, one of them being
wave powered devices.
There are three different types of hydrokinetic devices. The first type is a floating
oscillating body. There are two subcategories to this, the first being a point absorber
which is a buoy device. This device either floats on the surface of the water or below the
water and it moves up and down with the waves at a certain point. The second
subcategory is attenuator which is also known as "the snake generator." These are long
buoys that are segmented. When a wave hits, each part of the buoy moves at different
times and heights. The convertors that are in the parts that connect the segments move
around to convert the kinetic energy to electrical energy. The second type is the
overtopping device. Waves fill a reservoir that increases water pressure. The water is then
released back into the ocean. This falling water spins turbines to create energy. The third
type is the terminator device which is an oscillating water column. Air is present in one
chamber. The moving waves cause a rise and fall of the water level within that chamber
causing the air inside to compress and decompress. That motion moves a turbine to create
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energy ("Ocean Wave Energy"). A convertor converts the energy to generate power in
each case.
The simplest is the first device which works in this way: the mechanical energy is
taken from the waves and turned into electrical energy by using a generator. What
happens is that the waves move a buoy (that is placed at the antinode) up and down. The
motion of the buoy causes a magnet or multiple magnets to move up and down inside a
copper wire coil. The motion of the magnets creates a current within the coil. The current
is carried from the coil to a circuit that is connected to a capacitor. The electrical energy
is then stored in that capacitor. It is measured by using a voltmeter that measures the
energy in volts.
In this experiment, the researchers tested some possible factors for varying
voltages to have information that allows engineers to collect more energy. These
adjustments included changing the size of the buoy by using plastic balls of different
diameters and adding a different number of magnets to a larger magnet that was always
used. The buoys were created by drilling holes in plastic balls and attaching a steel rod
into it. The steel rod went inside of a generator (a flashlight). A magnet came with the
flashlight. The second factor was tested by adding a certain number of smaller
neodymium magnets to the flashlight's magnet. It was tested whether these adjustments
had a significant effect on the voltage collected by the energy generator. It was also
determined which combinations of these adjustments, and how much they were adjusted
affected the intensity the most.
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Environmental engineers and civil engineers can use this information to be more
efficient and cut costs. If there is no significant difference in size, the engineers can save
money by using less material on the buoy since the same voltage is collected by different
sized buoys. If not, then the engineers will know that to change the amount of voltage,
the size of the buoy must be changed. Engineers will also know whether the voltage
changes due to increase in the number of magnets, or in other words, a higher magnetic
field. They can use this information to be more efficient and cost effective. This
information can also bring power to third world countries.
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Review of Literature
Renewable energy is a very popular area of study right now. With global
warming and the diminishing supply of fossil fuels, people are looking for new energy
sources. Some popular sources are solar energy, wind energy, and hydro energy. Of these
three, water is the most reliable power source because, unlike sources such as solar and
wind, water is always constant (Daigneau). The more popular forms of hydro energy are
dams and water wheels. Some less known forms of hydro energy are rainwater devices,
river devices, and the new field of wave-powered devices.
Ideas and concepts for wave energy have existed since the 1800's but it was not
until 1940 that a real scientific interest was taken into it. A Japanese navy officer named
Yoshio Masuda was the pioneer for this new interest ("Wave Energy Utilization").
Masuda created one of the three main types of wave generators: the oscillating water
column. A real interest arose in wave energy during the oil crisis in the 1970's. After the
crisis ended, funding was majorly reduced and wave energy was almost forgotten about.
Many small models were created to try to harness waves, but a large interest did not
resurge until 2008 due to the energy crisis the world is facing today.
To begin to understand hydro energy, one needs to know about hydrokinetic
energy. Hydrokinetic energy is energy that is collected from the motion of fluids (water)
and converted into some useful from of power, usually electricity (Crawford). There are
many different types of hydrokinetic devices, but there are three main categories that they
usually fall under. The first category is the floating oscillating body which has two
subtypes: the point absorber and the attenuator. The point absorber either floats on the
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surface of the water or below the water and it moves up and down with the waves at a
certain point. The attenuator, also known as "the snake generator," is a long buoy that is
cut into segments and each segment is connected to the next. Since the attenuator is
segmented, each segment experiences the wave at a different time and it experiences a
different wave height. The convertors in the segments convert the energy as the waves
hit. In the attenuator, there are multiple convertors whereas there is only one converter in
a point absorber. The second type is the overtopping device in which waves fill a
reservoir. When the water pressure reaches a certain point, the water is then released back
into the ocean. This falling water spins turbines to create energy. The third type is the
terminator device which is an oscillating water column. The OWC acts like a piston in its
up and down motion. Simply put, there is air in one chamber and when the wave comes it
raises the water level in that chamber causing the air to compress and decompress. The
compression and decompression of the air forces a turbine to move and create energy
("Ocean Wave Energy"). This experiment will focus mostly on the point absorber
floating oscillating body.
A hydrokinetic device that floats on the surface of the water is called a floating
oscillating body ("Wave Energy Utilization"). As the buoy moves up and down due to the
waves, it gains kinetic energy. The buoy is connected to an electric generator which is a
device that converts kinetic energy into electric energy (Farthing). The movement of the
buoy causes magnets to move inside a coil ("Wave Tank I - The Duck Gen"). The coil
can then be connected to a circuit, a capacitor, or anything that stores the energy. The
movement of the magnets inside the coil creates electric energy which is then stored in
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the capacitor ("Wave Power"). The researchers of this experiment have done something
similar to this.
The size of the buoy in a floating oscillating body is important. A buoy that has a
larger volume will displace more water. Archimedes' Principle can attest to this claim
because it states that an object submerged in fluid displaces an amount of fluid equal to
the volume of that object. In other words, the buoyant force is equal to the weight of the
amount of fluid displaced by that object. Buoyant force is density of the object times
gravity times the volume of the object ("Kopot"). The larger the buoy is, the larger its
volume is, and the larger the buoyant force. If the buoy is larger, it will have more
buoyant force. When there is more buoyant force, the buoys have more potential to
generate more energy because the magnets in the generators move more.
One other thing that affects how much energy is collected is the generators, more
specifically the magnets inside the generators. The magnets change the mechanical
energy of the waves into electric energy in floating oscillating bodies. The movement of
the magnets inside the coil is what changes the mechanical energy. Faraday's Law can
attest to that statement since it states that "any change in the magnetic environment of a
coil of wire will cause a voltage (emf) to be 'induced' in the coil" ("Faraday's Law"). The
voltage that is produced through induction makes the current flow. The more coils there
are, the larger the number of electrons that are present. That increases the current flow.
When there are no waves, there is no change in the magnetic environment. But when the
waves hit, the buoy moves causing the magnets in the generator to move. When the
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magnets move there is a change in the magnetic environment. The more magnets there
are, or the more powerful the magnet, the more electrical energy there will be (Ahmed).
Many companies have done projects that inspired this experiment. Projects such
as Lysekil are similar to this experiment except for the fact
that both of these projects use turbines to generate their
power. Seen in Figure 1 is the Lysekil device. Lysekil's
generator is under the water, while the MMSTC researchers'
device has its generator hanging above the water. It is similar
in that the movement of the Lysekil buoy causes a rope to
move which moves magnets inside their generator ("Wave
Figure 1. Lysekil Device
Power Project").
The second project that related to this experiment was the AquaBuOY. It is
similar to the Lysekil device. When the buoy moves,
it causes pistons to move. Instead of using magnets,
the AquaBuOy used the force of the water inside the
cylinder to generate power (Chapa). Again, the
generator is under the water. Figure 2 shows a
diagram of how AquaBuOY works.
Figure 2. AquaBuOY
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Both of these projects have similarities with the experiment that the MMSTC
researchers performed. Such similarities are the fact that all three use buoys and a
generator. There are pistons that move an object up and down to create power. The only
big difference is that these devices are offshore devices so their generators are
underwater. The experimenters at MMSTC had their generator suspending from a base.
The experimenters had a smaller setting in mind than the ocean. They wanted to make
their device work in rural areas near rivers and lakes instead of the ocean like the large
offshore devices.
These hydrokinetic devices can be useful for many reasons. Many third world
countries are in need of cheap power sources to reach areas off the grid. Large companies
do not bring their energy to places outside of the main cities. Making smaller versions of
these large products would help the people living in more rural areas by providing
electricity (Headrick).
Hydrokinetic devices are also very reliable. Solar energy is highly expensive to
harness and solar panels create a glare that is harmful to the eyes. Wind energy cannot
always be harnessed because the wind is not constant. Hydro energy can be easily
harnessed because water is constant and there is little to no damage involved with most of
the devices (Jouanne), although dams can be harmful to ecosystems.
There are some problems with creating these devices, though. One would be that
it cannot be guaranteed that the device works and will do what is intended until it is built
and onsite (Jones). This doubt discourages companies from funding these projects.
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Creating smaller scale versions of the larger projects would be beneficial to the
companies. They can easily identify problems and fix them for a large scale investment.
Renewable energy is becoming a lot more popular, especially hydrokinetic
energy. It is in high demand now that fossil fuels are causing problems for the Earth.
Companies have made very large floating oscillating bodies, but creating smaller versions
of them would be beneficial to rural areas and third world countries. This research can
also benefit the companies creating the large devices by providing a more efficient way to
harness the energy.
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Problem Statement
Problem Statement:
To determine the effect of the diameter of the buoy and number of magnets of an
energy generator on the voltage collected from a wave generator.
Hypothesis:
The diameter of the buoy and the number of magnets will significantly affect the
voltage collected from the energy generator.
Data Measured:
The independent variables in this experiment are the different sizes of the buoys
and the number of magnets that is added onto the generator. The sizes of the buoys are
based on their diameters of 10 cm, 15 cm, and 20 cm. The number of magnets that are
used are 2 magnets, 4 magnets, and 6 magnets added. The dependent variable is the
amount of energy that the researchers will collect in volts. The amount of energy
collected will be measured by a voltmeter. If there is any significance between the
different sized buoys, it will be determined through a two-factor DOE test.
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Experimental Design
Materials:
(6) Neodymium Magnets (0.25”
diameter)
(1) Large Neodymium Magnet (1.18"
length x 0.59" diameter)
Sharpie
Timer
Large Paperclip
(3) Assorted Weights (5, 10, 15 lbs)
Storage Bin (54 gallons)
(3) Hand-Made Buoys
Water (10 gallons)
Wave Generator
Wood Clamp (4 ft)
Escort EDM-83B Multimeter
(0.004 to 400 volts)
Energy Generator
Procedure:
1. Fill the storage bin 17 cm from the bottom with water.
2. Place the wave generator (Appendix B) into the storage bin on the left side of the bin
(the shorter end).
3. Adjust the energy generator (Appendix A) so it is suspended over the tub (Figure 3).
4. Insert the large magnet with the necessary amount of magnets for the first randomized
trial of two magnets, four magnets, or six magnets on top of it.
5. Insert the cork (Appendix A) so that it fits tightly inside the opening of the generator
(Figure 4).
6. Stick the rod of the desired buoy for this randomized trial (low buoy, standard buoy,
or high buoy) inside the generator through the cork.
7. Adjust the height of the energy generator's stand so the magnets are below the bottom
of the coil (Figure 5).
8. Measure 18 cm inside the bin from the bottom and mark it with a Sharpie.
9. Push the wave generator up and down to create waves that reach the mark that was
created for 3 minutes. The buoy and rod should move up and down making the
magnets move up and down.
10. Record the voltage from the charge capacitor (Figure 6).
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11. Discharge the energy generator by turning the flashlight on then touching the two
diodes (Figure 7) with the paperclip until the voltmeter reads zero.
12. Repeat steps 4 to 12 to complete the first DOE.
13. Repeat steps 4 to 12 for three more DOEs.
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Diagrams:
Figure 3. Set-up
Figure 4. Cork Fitting
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Figure 5. Magnet Placing
Figure 6. Inserting Voltage Probes to Read Voltage
Figure 7. Discharging the Generator with the Diodes
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Data and Observations
Table 1
Factors and Values
Diameter of Buoy (cm)
Standard
+
7.50
7.94
10.38
Number of Added Magnets
Standard
+
2
4
6
Table 1 shows the variables for the experiment and the values that were used. The
researchers had to create their own buoys. To do so, they used whatever differing sized
balls that were available to them. Considering that their work space (a storage bin) was
not very large, they had to use smaller buoys. The smallest buoy had a diameter of 7.50
centimeters, the standard buoy had a diameter of 7.94 centimeters, and the largest buoy
had a diameter of 10.38 centimeters. The researchers used the magnet that came with the
flashlight in each trial. The low magnet trials had only two neodymium magnets, the
standard used four, and the high used six. They were ordered this way because the
number of magnets added increases, the magnetic field increases in power and creates
more energy. As the researchers added magnets, the total height of the magnet increased.
There was not much room for the magnets to move inside the flashlight because the
flashlight is not that long. For this reason, the number of magnets added was kept at low
numbers.
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Table 2
Change in Voltage Collected in Volts of each DOE
Runs
Order
1
2
3
4
5
6
7
Number of
Diameter of
Added
Buoy (cm)
Magnets
Standard
+
+
+
Standard
+
Standard
DOE #1
0.134
0.021
0.081
0.120
0.010
0.174
0.145
DOE #2
DOE #3
0.099
0.024
0.044
0.134
0.005
0.195
0.055
DOE #4
0.123
0.023
0.015
0.055
0.058
0.182
0.110
0.113
0.025
0.062
0.074
0.026
0.291
0.098
Table 2 shows the order of the runs, the runs with the type of trial, and the results
of each DOE of the researchers’ experiment. The results show voltage measured in volts.
Table 3
Averages of Testing Results
Runs
Diameter of Number of
Buoy (cm)
Added
Magnets
+
+
+
+
-
First
DOE
0.021
0.081
0.010
0.174
Second
DOE
0.024
0.044
0.005
0.195
Third
DOE
0.023
0.015
0.058
0.182
Fourth
DOE
0.025
0.062
0.010
0.174
Grand
Average:
Average
Voltage (Volts)
0.023
0.051
0.025
0.211
0.077
Table 3 shows the averages of the voltages of all of the runs, except the standards,
in all of the Design of Experiments. The grand average is also shown.
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Table 4
First DOE Observations
Order
Observations
Number
2
Day 1. Stand shook a lot; magnets hit the side of the flashlight.
3
Day 1. Stand shook.
4
Day 1. Stand shook when waves were created.
6
Day 1. Buoy went under the water.
Table 5
Second DOE Observations
Order
Observations
Number
2
Day 2. Stand shook a lot.
Day 2. Stand was too low. Magnets hit the top of the energy
5
generator.
Table 6
Third DOE Observations
Order
Observations
Number
2
Day 3. Stand was slightly shaky.
Tables 4, 5, and 6 show the observations for the four DOEs. Day 1 was a Friday
and the researchers were still getting accustomed to running trials. For this reason the
waves were not always consistently hitting the marked line. That in turn caused the stand
to shake. The next trials were done on day 2 which was a Monday. Two days had passed
since the last trials were run. Over those two days, the plastic storage bin expanded and
researchers had to use a wood clamp to bend the bin back into its original shape. Day 3
was a Wednesday and day 4 was a Thursday. By those two days, the researchers knew
how to adjust the stand so it would not shake and had consistency in creating waves. All
waves were created by Researcher 1.
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Data Analysis and Interpretation
Data was collected using a comparative experiment to find how diameter of a ball
and number of magnets affects the amount of voltage collected. A control,
randomization, and replication were used in order to ensure accuracy in the data
collected. The control was the standard trials. A control was used to limit the effect of
lurking variables on the data. Randomization was done in order to further reduce any
possible bias, and replication was used to ensure that the most accurate measurement
possible was taken. The replication was done by performing four DOEs and then
averaging the data from each one. Averaging many data points accounts for any trials
where there might have been an error. The experiment that was done was analyzed using
a two-factor Design of Experiment.
Table 7
Factors
Factors
Diameter of Ball
(cm)
Number of
Magnets
(-) Values
Standard
(+) Values
7.50
7.94
10.38
2
4
6
Table 7 shows the experimental values that were used in the experiment. The two
factors were diameter and number of magnets. The low, standard, and high levels for
diameter were 7.50 cm, 7.94 cm, and 10.38 cm. The low, standard, and high values for
pressure were 2 magnets, 4 magnets, and 6 magnets.
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Single Factor Effects:
Factor: Diameter (D)
Effect of Diameter
0.250
Voltage (v)
Table 8
Effect of Diameter
+
0.025
0.023
0.211
0.051
Avg: 0.118
Avg: 0.037
0.200
0.150
0.118
0.100
0.050
Effect =
(0.037 - 0.118) = -0.081
0.037
0.000
-1
1
Diameter
Figure 8. Effect of Diameter
Table 8 shows the resulting voltages when diameter was low and when diameter
was high. Figure 8 shows how voltage changed as diameter went from low to high. As
diameter increases, voltage decreases by 0.081 volts.
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Factor: Magnets (M)
Effect of Magnets
0.250
Voltage (v)
Table 9
Effect of Magnets
+
0.051
0.023
0.211
0.025
Avg: 0.131
Avg: 0.024
0.200
0.131
0.150
0.100
0.050
Effect =
(0.024 – 0.131) = -0.107
0.024
0.000
-1
1
Magnets
Figure 9. Effect of Magnets
Table 9 shows the resulting voltages when magnets were low and when magnets
were high. Figure 9 shows how voltage changed as magnets went from low to high. As
magnets increase, voltage decreases by 0.054 volts.
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Interaction Effect:
Diameter and Magnets
0.250
Interaction of Diameter and Number of Magnets
Effect = (0.023 – 0.051)/2 – (0.025 – 0.211)/2 =
0.067
Voltage (v)
0.211
Table 10
Diameter and Number of Magnets
Magnets (-) Magnets (+)
Diameter (+)
0.051
0.023
(solid segment)
Diameter (-)
0.211
0.025
(dotted segment)
0.200
0.150
D(-)
0.100
0.051
0.050
0.000
0.025
D(+)
-1
0.023
1
Magnets
Figure 10. Diameter and Magnets
Table 10 shows the resulting voltages when diameter and ground magnets are low
and high. Figure 10 shows the interaction between diameter and magnets. Segment D(-)
is the dotted line segment for when diameter is low and magnets go from low to high.
Segment D(+) is the solid line segment for when diameter is high and magnets goes from
low to high. The line segments for both low and high diameter show that there is a
possible interaction between diameter and magnets. The expected voltage for low
diameter is around 0.118 volts (Figure 7), but when magnets go from low to high, low
diameter goes from 0.211 to 0.025 volts. This is a big difference from the expected value
for low diameter of 0.118, meaning that magnets likely had an effect. This is similar to
the expected voltage for high diameter, meaning that there is a possible interaction
between diameter and magnets.
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Grand Average of all trials = 0.077
Overall Effects of Single Factors:
Effect of Diameter (D) = -0.081
Effect of Magnets (M) = -0.107
Interactions Between Factors:
Effect of Diameter and Magnets (MD) = 0.067
Prediction Equation:
Ŷ = 𝐺𝑟𝑎𝑛𝑑 𝐴𝑣𝑒𝑟𝑎𝑔𝑒 + 1/2𝐷 + 1/2𝑀 + 1/2𝐷𝑀 + 𝑛𝑜𝑖𝑠𝑒
Ŷ = 0.077 + −0.081/2(𝐷) + −0.107/2(𝑀) + 0.067/2(𝐷𝑀) + 𝑛𝑜𝑖𝑠𝑒
Ŷ = 0.077 + −0.041(𝐷) + −0.054(𝑀) + 0.034(𝐷𝑀) + 𝑛𝑜𝑖𝑠𝑒
Figure 11. Prediction Equation
Figure 11 shows the Prediction Equation used to predict experimental values. This
equation includes the grand average of all trials except standards, the two main effects,
the interaction effect, and noise.
Graph of Standards:
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Twelve Standard Trials
0.250
Voltage (V)
0.200
0.150
0.100
0.050
0.000
0
1
2
3
4
5 6 7 8
Trial Number
9 10 11 12
Figure 12. Graph of Standards
Figure 12 shows a graph of all twelve standard trials that were performed. The
standards do not show any pattern but are not extremely consistent, which led to the
conclusion that the experimental results could possibly be inconsistent or invalid because
there was not a consistent control.
Figure 13. Dot Plot of Effects
Figure 13 shows a dot plot of all three effects. The variable M denotes the effect
of the number of magnets that were added on. The variable D represents the effect of the
size (diamter) of the buoy. The factor DM denotes the interaticiton effect of the number
of magnets added and the size of the buoy. All of the effects are less than 0.160 away
from zero and the interaction between diameter and magnets has the largest effect.
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Test of Significance:
2 × |𝑅𝑎𝑛𝑔𝑒 𝑜𝑓 𝑆𝑡𝑎𝑛𝑑𝑎𝑟𝑑𝑠|
2 × |0.145 − 0.055|
2 × |0.090| = 0.180
Figure 14. Test of Significance
Using the test of significance shown in Figure 14, the range of standards and the
rules of determining significant effects, none of the three effects were determined to be
significant. An effect was considered significant if the absolute value of the effect was
greater than twice the range of standards. The absolute values of the effects for diameter,
magnets, and the interaction are 0.081, 0.107, and 0.067 respectively. None of these
effects were greater than or close to 0.180; therefore, no effects are significant.
Parsimonious Prediction Equation:
Ŷ = 0.077 + 𝑛𝑜𝑖𝑠𝑒
Figure 15. Parsimonious Prediction Equation
Figure 15 shows the Parsimonious Prediction Equation. This equation includes
the grand average of the data and the vital few which are the factors that had a significant
effect on the results. None of the effects were considered significant, therefore none of
the effects are used in this equation. Noise is a term ised to express the effets of any other
lurking variables that may have affected the results of the experiment.
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Conclusion
This experiment was conducted to test whether or not the diameter of a buoy and
the number of magnets added affect the voltage of energy created by waves. The
researchers rejected their hypothesis that all the factors would have an effect on voltage.
On average, the trials that had the low diameter and the low number of magnets (2) added
produced the maximum voltage received. On average, the trials that had the high
diameter and the high number of magnets (6) added produced the minimum voltage. The
wave generator was placed on one side of a large storage bin that was filled with water to
a height of 17 centimeters. The wave generator was pushed up and down to create waves.
These waves moved a small, medium, or large sized ball depending on the trial. The ball,
which served as the buoy, moved a large magnet with either two, four, or six smaller
magnets added to it depending on the trial. The magnets moved through a coil that
generated electricity, which was recorded by a voltmeter.
It was believed that the number of magnets and buoy size would significantly
affect the voltage collected from the energy generator. A two factor Design of
Experiment was used to test each effect and their interactions. That means that every
factor was tested was for significance. The researchers rejected their hypothesis that the
diameter of the buoy and the number of magnets added were both significant in affecting
the voltage collected by the energy generator.
The first effect that was tested was the diameter of the buoy. According to
Archimedes Principle, an object that is submerged in fluid displaces an amount of fluid
equal to the volume of that object. This means that an object floats if it displaces the same
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amount of fluid as the volume of the object. In this experiment balls (spheres) were used
as the buoys. The volume of a sphere is four thirds pi times the radius of the sphere
cubed. This means that the larger balls had a larger volume and displaced more water.
Buoyant force is equal to the volume of the object times the density of the fluid times the
volume of the fluid displaced times the constant g (see Figure 16). The density of the
water stays constant and g stays constant so the only thing changing is the volume
(Kopot).
FB  m fluid * g   fluid * V * g
Figure 16. Equation for Buoyant Force
The larger balls have a larger volume so they also have a larger buoyant force.
The buoys with the larger buoyant force will move the magnets more because the
buoyant force pushes on the rod to move the magnets. The more the magnets move, the
more voltage should be generated. However, the researchers found that using the small
buoy resulted in a larger volume than the large buoy. This could have occurred because
of the large buoy's mass. The large buoy had a mass of 98 grams while the small buoy
had a mass of 33.5 grams. The buoyant force easily pushed up the small buoy because it
was not that heavy, but the large buoy's mass was significantly higher than the small
buoy so it was harder for the buoyant force to push up on the large buoy.
The second effect that was tested was the number of magnets added to the large
magnet that was already present. During the course of research, the researchers learned
that the number of magnets moving through a coil should have an effect on voltage.
According to Faraday's Law, the movement of a magnet inside a coil of wire changes the
magnetic field which induces a current (Hare). In this experiment, a magnet was moved
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in and out of a coil. This movement changed the magnetic field which induced a voltage.
The voltage was then stored in the capacitor. As the number of magnets increases, the
change in magnetic field increases. Due to that increase in magnetic field strength, the
voltage should also increase.
According to the researchers’ experiment, the number of magnets added to the
energy generator does not have an effect on the voltage collected. This should not be the
case. As stated previously, “the more magnets you have, the higher the magnetic field is.
That means it'll generate more electricity” (Ahmed). Some reasons for the experiment
giving false results could be that the change in magnetic field was not always created.
Also, for the high magnet trials the magnets did not always fully come out of the coil
because the buoy would move sideways. That would cause the rod to move at an angle
inside the generator. Because of that motion, the magnets would be angled and they
would hit the side of the generator and would not move up and down. The magnetic field
is then at an angle with the wire. When the angle between the magnetic field and the wire
increases, the voltage decreases because the force on the electron is reduced. This could
have made the change in magnetic field lower than it was on the other trials.
A design flaw was that the researchers did not have access to better equipment.
The researchers were on a budget and could not build a better contraption to create the
waves in. The storage bin had ridges in the sides which could have affected the waves as
they hit the buoy. The storage bin was made of plastic and when a large amount of water
was put into it, the bin expanded which affected the waves by making the waves shorter.
To perform this experiment better, the researchers could have used something that is
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meant to hold water like a fish tank since it would not expand when water is put in it.
There was also an issue of time. The rod and buoy would not always stay inside the
generator since the cork was not very sturdy. If there was more time allotted, the
researchers could have built a better energy generator so the rod would stay in place
inside the generator or they could have created a more sturdy cork. It was also tedious to
create waves by hand and to keep the waves going at a constant rate. If there was more
time allotted the researchers could have prepared and built a better wave generator that
created waves on its own at a steady rate so there is less room for human error. They also
could have done more trials for more data, which would have given better averages.
Another option would have been to use less added magnets or use a larger generator to
make sure the magnets had enough room to move up and down. To enhance this
experiment, the researchers could have had more time.
For further research, the experiment can be conducted in a river or lake to see if
there is a large-scale effect with the factors. The experiment can even be done in a small
pond or pool to see whether the amount of water changes the voltage collected. Future
researchers could also test other factors like different types of magnets or different shapes
of buoys that were not used in this experiment. Researchers in the future can take note
that the voltage generated by the hydrokinetic device varies with the balance between
size of the buoy and magnets. When the two factors are proportional, it creates the most
voltage. Lastly, future researchers can change the rate at which the waves hit the buoy
and see which creates more energy, in other words change the frequency of the waves.
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Acknowledgements
The researchers would like to thank Dr. Jonathan Hare for inspiring them to
perform this experiment with his YouTube videos. They would also like to thank Mr.
Hamid Ahmed for being their professional contact and giving them insight on their
research experiment. The researchers would also like to thank Mr. McMillan and Mr.
Supal. Both teachers offered their wisdom and knowledge during the entire research
process. They helped the researchers in building the parts and understanding the science
behind the experiment and in keeping the researchers calm during stressful times. Finally,
the researchers would like to thank Mrs. Gravel for providing emotional support when
anything went wrong and for checking over our papers.
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Appendix A: Building the Energy Generator
Materials:
Forever Flashlight III by Excalibur
(3) Steel Rod (3/8 in in diameter and 9.5
in in length)
(2) Dual Clamps
(1) Beaker Clamp
(2) Thread Lab Stand Rods
Lab Stand Base
(3) Hollow Plastic Balls (7.5, 7.94, and
10 in diameter)
Hot Glue Gun
Plastic Tubing (2 in diameter and 1.6 in
length)
Duct Tape
Drill
Procedure:
1. Unscrew the lens and remove the outer casing of the flashlight (Figure 17). Then
set the flashlight aside.
2. Screw one of the thread lab stand rods into the lab stand base.
3. Use a dual clamp to attach the second lab stand rod to the first one (Figure 18).
4. Attach the beaker clamp to the other dual clamp.
5. Attach the generator to the beaker clamp (Figure 18) with the open side down.
6. Set the generator aside.
7. Wrap the duct tape around the tubing multiple times to create the cork. Wrap it
until the cork fits snuggly in the opening of the generator (Figure 19).
8. Use a drill to drill a hole 3/16 of an inch into each ball at the top and bottom.
9. Stick the steel rods into the balls and seal them with hot glue (Figure 20). The
largest ball should have 6 in of the rod sticking out from one side, the standard
ball should have 6.7 in of the rod sticking out, and the smallest ball should have 7
in of the rod sticking out.
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Lewandowski - Mubashira
Diagrams:
Figure 17. Electric Generator
Figure 18. Electric Generator
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Figure 19. Cork
Figure 20. Finished Buoys
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Appendix B: Building the Wave Generator
Materials:
PVC Pipe (4 in diameter)
(2) End Caps
Procedure:
1. Put one cap on each end of the PVC pipe (Figure 21). Make sure it is on tight.
2. Use a hand to move the pipe up and down to create waves.
Diagrams:
Figure 21. Wave Generator
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APPENDIX C: Professional Consultant
Name: Sarah Lewandowski
Najah Mubashira
Research Topic: Difference in Voltage of Energy Collected By Changing The Buoy Size
of a Wave Generator
Professional Contact Information
Name: Hamid U. Ahmed
Title: Project Engineer
Organization: Black and Veatch Corporation
Phone (area code and extension): 1-913-458-7620
Email: hamida@bv.com
Mailing Address: B34 10950 Grand View Drive Overland Park, Kansas 66210
Dialogue Information
1. Contact Goal
Our goal is to learn more about generators and what the role of a magnet in a
generator is. We would also like to learn more about energy.
2. At least three potential questions to help reach your goal
A. Does the size of the magnet affect the amount of energy created?
B. What decides the amount of energy created?
C. Would a larger buoy collect more energy?
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Lewandowski - Mubashira
3. Additional Information/Reply
Glad to know you are working for a project which is the basic for Electrical
Industry. A moving object in a magnetic field will induce electricity in the moving
object; this is the basic concept. You have taken a very smart idea; that you have kept
the object static and moved the mag field on it. The magnet is the source of Mag field
and you are moving this inside the object which is the coil. The variable factors here
are three. #1 the coil more the turns more electricity it should generate, #2 is the
magnetic field more power full the field more electricity will generate, #3 is the force
of moving more power full the force of moving more power will generate.
The way you are making in my idea it would create some electricity but you need
a power full magnet more power full it is more will be generated. But it will also
create some problem such powerful magnets will get bigger in size and will need
bigger hollow space inside the coil, so keep an eye on the hollow space and the
magnet should not touch the coil in that case it may scratch and coils insulation may
get damaged. A damaged coil will generate electricity but will short circuit it and no
current will flow to the capacitor which you are going to connect. Take a smaller size
power capacitor and in the beginning check the voltage once you are sure of the
voltage than only connect the capacitor. You will notice the moment you have
connected the capacitor the voltage will go down, find an answer this why the voltage
go down when the capacitor is connected. Also look for an answer what decide the
voltage level.
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Lewandowski - Mubashira
To generate electricity you have to work real hard to keep the float movement
inside the coil. Check the connections and the insulation in the connection places
should be carefully removed take care in doing this. Check also the continuity of the
coils; you need ohm meter to check I hope you have multi meter or ohm meter which
normally used for voltage and ohm measurement. Some meters are also have current
measurements mostly very low level DC current but little expensive one may have
AC current measurements. Learn the use of ohm meter or multi meter before using; I
believe your teachers know about the use of it.
Volt measurement is easy, you already know about it, current measurement will
also be easy but power measurement will be little less easy, you will need a power
meter for this, but first of all you generate the voltage.
Thank you and feel free to call or mail me, I believe you have my office number
do not hesitate to call during office hours in the office.
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Lewandowski - Mubashira
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